Yarn float controller means for circular knitting machines

ABSTRACT

A multi-feed circular cylinder and dial type knitting machine set up to produce floated yarn effects and having at each feed a float controller device. Yarn missed by needles is engaged by controller and maintained at required angular relationship between it and a stitch cam at the feed. Device comprises (a) a yarn guide plate secured to the dial cam plate and having a hinge pin and a spring-locating hole, and (b) a removable float controller having in a bifurcated tail end thereof open-ended slots to engage the hinge pin, and an arm-like forward extension notched to receive a float of yarn. The controller straddles the yarn guide plate. A helical compression spring supported at one end by a projection on the float controller fits in the springlocating hole.

United States Patent Farmer et al.

[ June 17, 1975 YARN FLOAT CONTROLLER MEANS FOR CIRCULAR KNITTING MACHINES [75] Inventors: Ernest Leonard Farmer, Leicester;

Osmond Herbert Ecob, Blaby, both of England [73] Assignee: Wildt Mellor Bromley Limited,

Leicester, England [22] Filed: Dec. 11, 1973 [21] App]. No.: 423,787

[30] Foreign Application Priority Data Jan. 16, 1973 United Kingdom 2169/73 [52] US. Cl 66/19; 66/125 R; 66/131; 66/141 51 Int. cm D04B 15/54 [58] Field of Search ..66/l3l, 19,125 R, 141

[56] References Cited UNITED STATES PATENTS 1,335,633 3/1920 Ames 66/131 1,827,660 10/1931 Kent 66/131 3,226,954 l/l966 Fregeolle 66/125 R 3,529,442 9/1970 Gelber et a1... 66/141 X 3,545,234 12/1970 Forrester 66/125 R FOREIGN PATENTS OR APPLICATIONS 542,526 1/1942 United Kingdom 66/131 Primary ExaminerWm. Carter Reynolds Attorney, Agent, or Firm-Larson, Taylor and Hinds [5 7 ABSTRACT A multi-feed circular cylinder and dial type knitting machine set up to produce floated yarn effects and having at each feed a float controller device. Yarn missed by needles is engaged by controller and maintained at required angular relationship between it and a stitch cam at the feed. Device comprises (a) a yarn guide plate secured to the dial cam plate and having a hinge pin and a spring-locating hole, and (b) a removable float controller having in a bifurcated tail end thereof open-ended slots to engage the hinge pin, and an arm-like forward extension notched to receive a float of yarn. The controller straddles the yarn guide plate. A helical compression spring supported at one end by a projection on the float controller fits in the spring-locating hole.

9 Claims, 3 Drawing Figures SHEET PATENTED JUN 1 7 I975 YARN FLOAT CONTROLLER MEANS FOR CIRCULAR KNITTING MACHINES This invention relates to circular knitting machines. and has reference particularly to multi-feed circular knitting machines of the cylinder and dial type capable of being set up to produce floated yarn effects in the knitted fabric.

Although it is principally the intention to apply the invention to such a multi-feed machine having a rotary needle cylinder and dial and a stationary cylinder cam box and dial cam plate, there is no limitation in this respect since the invention could be applied to a stationary cylinder and dial machine having rotary cam systerns.

The invention, moreover, is primarily concerned with a multi-feed cylinder and dial machine capable of being set up to produce so-called blister fabric, i.e. jacquard fabric raised on its outer face by various arrangements of dial miss effects. In the production of blister fabric which may, if desired, include colours, dial needles non-knit at a patterning feed or feeds and, at the or each corresponding feed, predetermined, e.g., spaced, ones only of the cylinder needles knit so that unknitted floats occur and extend between these cylinder needles. The lengths of the floats depend upon the numbers of non-knitting cylinder needles which separate those cylinder needles which are caused to clear, take yarn and knit.

Depending on the number of feeds on the machine and the lengths of the floats, it sometimes happens that an unknitted i.e., floating, portion of yarn extending between the feeder at a feed and the last needle to knit the yarn is so pulled as to assume an angle which is shallower than the comparatively steeper angle of the stitch cam. If this happens, then the next cylinder needle intended to take and knit the yarn at the same feed misses the said yarn and so fails to knit it; this is because the yarn floats above the steeply descending head of the needle as the latter is retracted by the stitch cam to knocking-over point. As a consequence, the yarn that is missed by the needles descending the stitch cam is carried round by the last needle to take it to the next feed; meanwhile the needles which should have taken the yarn at the previous feed are pressing the old loops off and this results in faulty fabric.

With the aim of obviating this difficulty we have previously proposed, in our prior U.S. Patent Specification Ser. No. 3,545,234, to provide, at each feed of a multifeed circular knitting machine of the cylinder and dial type capable of being set up to produce floated yarn effects, a float controller including an element adapted to be spring loaded in an operative position in which it is so arranged that, in normal working conditions when the needles are knitting, the yarn being knitted runs clear of the said element, whereas where the said yarn is missed by the needles the resulting float engages the element suchwise that the required angular relationship between the yarn and the corresponding stitch cam at the feed is maintained. Such a float controller, as so far very broadly considered will, for convenience be hereinafter called a float controller of the form herein referred to. Each such float controller, in the prior arrangement is also adapted to be latched in its operative position against the spring influence and is releasible and withdrawable, under this influence, from its operative position in consequence of the exertion laterally thereon of light pressure so as to enable desired changes in knitting to be made without wholly removing the controller element.

Moreover, each of the float controller elements in the prior arrangement was adapted to function as a detector to detect the presence of and avoid damage being done by any undesirable body, such as a faulty needle or a slub of yarn, coming into contact with the controller-detector element. For this purpose there was provided in association with each such controllerdetector element an electrical switch designed to be included in an electrical stop motion circuit whereby in consequence of a lateral displacement of the element as aforesaid release of the element results in stoppage of the machine.

It is to be clearly understood that, in our prior arrangement just described, the float controller cum electrical stop motion device at each feed of the machine was naturally associated with but quite separate and distinct from the yarn guide at that feed. These guides, in the form of yarn guide plates, were mounted on the dial cam plate and adapted also to function as needle latch guards.

Although our prior yarn float controllers cum electrical stop motion devices are quite efficient and satisfactory in cases where there is adequate room, it is becoming impracticable to use them because of the increasing numbers of feeds with which circular knitting machines of the kind concerned are nowadays being provided, thus necessitating the consequential provision at the relevant locations around the machine of far more yarn float controllers cum electrical stop motion devices and electrical wiring connections than heretofore. This, in turn overcrowds and makes practically inaccessible the dial cam plates to which the said devices and the wiring connections are attached.

Accordingly, the primary object of the present invention is to provide an improved arrangement in which float controllers of the form herein referred to are mounted in out of the way positions to provide more accessibility to the machine. The improved arrangement is designed also to secure other advantages hereinafter to be listed.

According to the improvement provided by this invention a yarn float controller of the form herein referred to is no long adapted tofunction adjunctively as a detector of an electrical stop motion device, and is mounted directly upon the corresponding yarn guide plate, i.e., in an out of the way position.

In a convenient embodiment of the invention, each float controller is so pivotally or hingedly mounted upon the corresponding yarn guide plate as to be readily disengageable and removable therefrom, spring means being provided between the said yarn guide plate and the controller so as normally to hold the latter in its operative position.

This arrangement incidentally enables the controller to safely yield upwardly if and whenever it is contacted and displaced by a faulty needle or slub of yarn; the spring means automatically returning the controller, after such displacement, to its active position to control a floated yarn.

Thus, in one advantageous arrangement, open-ended slots are formed in the body of the float controller to enable it to be removably engaged with a hinge pin on the corresponding yarn guide plate.

The operative end of the controller may be in the nature of an arm-like extension the extremity of which is notched to receive a float of yarn.

It is to be clearly understood that although the float controllers of this invention are not themselves directly combined with electrical stop motion devices, a multifeed circular cylinder and dial knitting machine to which such controllers are fitted will nevertheless usu' ally be equipped, at any appropriate locations remote from the float controllers. with electrical stop motion means.

In order that the invention may be more clearly understood and readily carried into practical effect, a pre ferred embodiment thereof as applied to a multi-feed circular knitting machine ofthe rotary cylinder and dial type will now be described. by way of example, with reference to the accompanying drawings, wherein.

FIG. 1 is a fragmentary side elevational view of so much of the machine as is necessary to show the application of the invention thereto and includes two feeds and associated yarn float controllers,

FIG. 2 is a detail vertical sectional elevation taken approximately on line II II of FIG. 1, and

FIG. 3 is a perspective view in exploded form, of one of the yarn float controllers together with the yarn guide plate upon which it is directly mounted.

The portion of the machine shown in FIGS. 1 and 2 comprises a rotary needle cylinder 1 having therein latch needles such as 2, a stationary cambox 3 fur nished with conventional knitting cam systems 4, a rotary dial 5, a stationary dial cam plate 6, and a bed plate 7.

Mounted on the dial cam plate 6 at the respective feeds F and F are yarn guide plates cum latch guards 8, each modified as compared with a conventional guide to include a hinge pin 10 and a spring-locating hole 12 (see FIG. 3). The hinge pin 10 protrudes from the opposite front and rear faces of the guide plate 8, and the hole in the latter through which a yarn Y is threaded and travels is indicated at 1 1. The hole 12 extends at right angles to the hinge pin 10.

Associated with each yarn guide plate 8 is a yarn float controller 14 which, as shown in FIG. 3, is mainly of inverted channel form with a bifurcated tail end comprising a pair of suitably spaced parallel portions which are slotted at 14a and 14b respectively. This bifurcated tail end of the controller 14 is thus adapted to straddle the yarn guide plate 8 and, by presence of the slots 14a and 14b, is enabled to locate on the hinge pin 10. The pivoted yarn float controller 14 associated with each yarn guide plate 8 is normally yieldably maintained in its working position shown in FIGS. 1 and 2 by a small helical compression spring 16. At one end, and as shown in FIG. 3, this spring 16 is engaged with and supported by a tongue or projection 18 on the float controller 14 and has its opposite end located in the aforementioned hole 12 in the guide plate 8.

The extended forward or outer end of each float controller 14 is in the nature of an upwardly curved or arcuate arm 20 having in its extremity a downwardly directed notch 20a in which a yarn Y locates during the creation of a long float as seen at the feed F in FIG. 1.

In normal working conditions, i.e., when the needles are knitting, a yarn taken by needle hooks runs clear of the notch 20a in the extremity of the arm 20, as de picted at feed F in FIG. 1, but, at any feed such as F in FIG. 1 where a yarn is missed by the needles, that is to say where the yarn is floated, the said yarn engages in the notch 20a.

Without the provision of the float controller arm 20, the yarn would be carried around by the last needle which has taken it, and would extend from the feeder at such a shallow angle that when the yarn is again required to be knitted by a subsequent needle, the yarn would be positioned too high to be accepted into the needle hook.

The arm 20 is, therefore, incorporated to ensure that the required angular relationship between the yarn and the stitch cam K is maintained substantially constant regardless of whether certain needles are knitting or missing the yarn.

The principal advantages of a float controller of the improved form can be summarised as follows:

1. It can be pre-set on its yarn guide plate, with the assistance of a gauge, before fitting on a machine.

2. It is less likely than some prior controllers to be accidentally displaced when in position on the machine.

3. It can be easily and quickly removed from one feed to another, according to requirements, when the machine is set up to produce blister fabric.

4. As previously mentioned, it automatically returns under spring influence to its active position to control a float yarn after being displaced by a faulty needle or a slab of yarn.

5. Because it is mounted directly upon a yarn guide plate, the dial cam plate is kept clear of lint catching assemblies.

6. It is less complicated than some prior float controllers in that it does not have any electrical stop motion connections attached to it.

We claim:

1. A multi-feed circular knitting machine of the type comprising a needle cylinder, a cylinder cam box, a needle dial and a dial plate, said machine being set up to produce floated yarn effects in the knitted fabric and wherein there is provided at each feed a stitch cam and at at least some feeds a float controller including an element adapted to be spring loaded in an operative posi tion in which it is so arranged that, in normal working conditions when the needles are knitting, the yarn being knitted runs clear of the said element whereas where the said yarn is missed by the needles the resulting float engages the element in such a way that the required angular relationship between the yarn and the stitch cam at the feed is maintained, characterized in that each said float controller is mounted directly upon a corresponding yarn guide plate secured upon the dial cam plate at its feed and is not itself adapted to funtion as a detector of an electrical stop motion and wherein each said float controller is so pivotally mounted upon its corresponding yarn guide plate as to be readily disengageable therefrom, and spring means are provided between each yarn guide plate and its respective controller for normally holding the latter in its operative position but enabling the controller to safely yield up wardly against the spring influence if it is contacted and displaced by a faulty needle or a slab of yarn.

2. A circular knitting machine as claimed in claim 1, wherein each yarn guide plate in addition to being formed with a hole through which a yarn can be threaded and travel, is provided with a hinge pin protruding from opposite faces thereof and has a springlocating formation, and wherein the associated removable float controller has a body which is formed for engagement with the hinge pin and is provided with a float-receiving extension, a spring retained by said spring-locating formation being arranged to bear on the float controller body.

3. A circular knitting machine according to claim 2, wherein the body of each float controller has formed therein open-ended slots to receive the hinge pin on the associated yarn guide plate.

4. A circular knitting machine according to claim 2, wherein said float receiving extension of each float controller is an arm-like forward extension which is notched to receive a float of yarn.

5. A circular knitting machine according to claim 3, wherein each float controller is mainly of inverted channel form with a bifurcated tail end comprising a pair of suitably spaced parallel portions in which the open-ended slots are formed, said portions being adapted to straddle the associated yarn guide plate.

6. A circular knitting machine according to claim 5,

wherein each float controller is provided, between the two spaced and slotted parallel portions of its bifurcated tail end, with a springengaging projection.

7. A circular knitting machine according to claim 4, wherein the arm-like forward extension of the body of each float controller is of an upwardly curved arcuate form having its notched extremity downwardly di rected.

8. A circular knitting machine according to claim 2, wherein the spring-locating formation of each yarn guide plate is a hole extending at right angles to the hinge pin.

9. A circular knitting machine according to claim 6, wherein said spring is a helical compression spring supported at one end by the spring-engaging projection of each float controller and at its other end is accommodated in the spring-locating hole in the yarn guide plate. 

1. A multi-feed circular knitting machine of the type comprising a needle cylinder, a cylinder cam box, a needle dial and a dial plate, said machine being set up to produce floated yarn effects in the knitted fabric and wherein there is provided at each feed a stitch cam and at at least some feeds a float controller including an element adapted to be spring loaded in an operative position in which it is so arranged that, in normal working conditions when the needles are knitting, the yarn being knitted runs clear of the said element whereas where the said yarn is missed by the needles the resulting float engages the element in such a way that the required angular relationship between the yarn and the stitch cam at the feed is maintained, characterized in that each said float controller is mounted directly upon a corresponding yarn guide plate secured upon the dial cam plate at its feed and is not itself adapted to funtion as a detector of an electrical stop motion and wherein each said float controller is so pivotally mounted upon its corresponding yarn guide plate as to be readily disengageable therefrom, and spring means are provided between each yarn guide plate and its respective controller for normally holding the latter in its operative position but enabling the controller to safely yield upwardly against the spring influence if it is contacted and displaced by a faulty needle or a slub of yarn.
 2. A circular knitting machine as claimed in claim 1, wherein each yarn guide plate in addition to being formed with a hole through which a yarn can be threaded and travel, is provided with a hinge pin protruding from opposite faces thereof and has a spring-locating formation, and wherein the associated removable float controller has a body which is formed for engagement with the hinge pin and is provided with a float-receiving extension, a spring retained by said spring-locating formation being arranged to bear on the float controller body.
 3. A circular knitting machine according to claim 2, wherein the body of each float controller has formed therein open-ended slots to receive the hinge pin on the associated yarn guide plate.
 4. A circular knitting machine according to claim 2, wherein said float receiving extension of each float controller is an arm-like forward extension which is notched to receive a float of yarn.
 5. A circular knitting machine according to claim 3, wherein each float controller is mainly of inverted channel form with a bifurcated tail end comprising a pair of suitably spaced parallel portions in which the open-ended slots are formed, sAid portions being adapted to straddle the associated yarn guide plate.
 6. A circular knitting machine according to claim 5, wherein each float controller is provided, between the two spaced and slotted parallel portions of its bifurcated tail end, with a spring-engaging projection.
 7. A circular knitting machine according to claim 4, wherein the arm-like forward extension of the body of each float controller is of an upwardly curved arcuate form having its notched extremity downwardly directed.
 8. A circular knitting machine according to claim 2, wherein the spring-locating formation of each yarn guide plate is a hole extending at right angles to the hinge pin.
 9. A circular knitting machine according to claim 6, wherein said spring is a helical compression spring supported at one end by the spring-engaging projection of each float controller and at its other end is accommodated in the spring-locating hole in the yarn guide plate. 